Will the real Chad Smith please stand up? Or, at the very least, take to the drum set.

The Red Hot Chili Peppers drummer just so happens to be a dead ringer for actor Will Ferrell, to the point that people apparently mistake them for one another.

"A lot of people think that it's me playing for the Red Hot Chili Peppers," Ferrell said during a Reddit "Ask Me Anything" in February. "But that would be an insult to Chad Smith. The truth of the matter is there is no Will Ferrell. Only Chad Smith."

After Ferrell took his joke to Funny Or Die, claiming that he really is Smith, the drummer (humorously) demanded that the actor stop impersonating him and challenged him to a drum-off.

Finally, on Thursday night, Smith's dream drum-off came to be. "The Tonight Show's" Jimmy Fallon had the doppelgangers on to determine once and for all who was who.

Before they got to the kits Fallon tried to settle this epic rivalry, which led to Ferrell and Smith "tricking" Fallon by pretending to be one another. (The best part of all of this is that none of them could keep a straight face.)

After failing to suss out the real story, Fallon kicked off their percussion duel.

In the end, Ferrell had to stick with what he knows best. More cowbell!